Sharpening Methodologies

[Teresa Jones]

I attended the hand plane freebie at Woodcraft this Saturday.

Part of the discussion was on sharpening. The series of 'grits' for sharpening stones given were 250, 600, 800, 1200, 4000, 6000, and 8000 or something close to this series. This particular discussion concerned different sharpening stones.

According to the presentation, 4000 is the threshold for sharpness with regards to woodworking. Also, he indicated that an Arkansas stone can only get you to 4000 but not beyond and that most plane blades are only sharpened to 1200 by the manufacturer.

Does anyone know the sandpaper equivalent to the 4000, 6000, and 8000 grit waterstones?

I have used waterstones in the past with some degree of success and I am tempted to return to them. The sandpaper is so much easier, though.

Appreciate your answers and thoughts.

TJ

[Tom Scott]

Teresa,
Kind of hard to say for sure since there can be variations between different brands of stones, but here is a link showing relative grit comparisons of different materials. Grits

I hope this helps.

Tom

[Kurt Loup]

I attended the hand plane freebie at Woodcraft this Saturday.

Does anyone know the sandpaper equivalent to the 4000, 6000, and 8000 grit waterstones?


TJ

Just a guess, but I'd say in the neighborhood of 1500 to 2000 grit.

Kurt

[Terry Beadle]

Dear Ms Jones,

My 2 cents. Waterstones are wonderful. You don't need all the different granularities. I would recommend a 800 to 1000 as a first step, then go to a 3000 muga ( Blue stone ), then go to a 6000 polish and if you like to a 8000. That will let you shave hairs easily. I also use a very fine polish from the folks at Tormec ( $7 a tube ) for those japanease chisels that have the harder steel. This makes them cut end grain pine smoothely with no tear out.

If that's too long a method, I also can recommend a 600 grit diamond stone followed by a firm buffing wheel with steel polishing compound applied. These two simple steps will put an edge on a plane blade with in a couple minutes effort. Very good to touch up an edge that's starting to dull.

Hope this helps.

Happy shavings

Terry

[Richard Gillespie]

I use to use water stones but I got tired of always having to flatten them before the next sharpening cycle.

I've gone back to the "scary sharp" method and find that the 2000 grit wet/dry sandpaper equates to my old 8000 water stone.

At Red Hill Corporation I saw 2500 grit wet/dry paper but I didn't buy it. I felt 2000 was fine enough.

[Lloyd Robins]

Hi! If you go to toolsforworkingwood.com, they have a section on sharpening which might help. They also sell sandpaper that is measured in microns. They say that a .5 micron is about 8000 grit and a .3 micron is about a 12000 grit waterstone. Good luck.

[Michael Campbell]

I use to use water stones but I got tired of always having to flatten them before the next sharpening cycle.

I've gone back to the "scary sharp" method and find that the 2000 grit wet/dry sandpaper equates to my old 8000 water stone.

At Red Hill Corporation I saw 2500 grit wet/dry paper but I didn't buy it. I felt 2000 was fine enough.

I did the same thing as you, but I do a dozen strokes on 2500 as well.

Incidentally, I've had really good service from here. I've bought a number of abrasive-y things from them and the prices and service are both good.

[Teresa Jones]

You guys deliver!!

Thanks everyone for the feedback.

I started out using the waterstones but I never got a hair shaving sharpness. Now I find out that you have to use the Nagura stone on the 6000 and 8000 stone or you get nothing. They are a bit messy, too.

I moved on to try the scary sharp and had my best luck yet in getting my chisels and plane blades sharp.

I think I need to revisit the waterstones, but keep the scary sharp setup and add some of the finer grits.

Again, thanks for all your feedback and references!

TJ

[Steven Wilson]

You guys deliver!!

Thanks everyone for the feedback.

I started out using the waterstones but I never got a hair shaving sharpness. Now I find out that you have to use the Nagura stone on the 6000 and 8000 stone or you get nothing. They are a bit messy, too.

I moved on to try the scary sharp and had my best luck yet in getting my chisels and plane blades sharp.

I think I need to revisit the waterstones, but keep the scary sharp setup and add some of the finer grits.

Again, thanks for all your feedback and references!

TJ

And eventually you'll try Shapton stones (ceramic water stones) and you'll enter sharpening nirvana - much faster than scary sharp, longer lasting flatness than typical waterstones, and a much finer finish than the others.

[Tom Scott]

And eventually you'll try Shapton stones (ceramic water stones) and you'll entery sharpening nirvana - much faster than scary sharp, longer lasting flatness than typical waterstones, and a much finer finish than the others.

Indeed. I received the 1000, 5000, and 8000 Pro Shaptons for X-mas, and they are great. They are everything you said.

Tom

[Scott Quesnelle]

If you want to compare scary sharp, waterstones and oilstones. Take a look at this page:

http://www.ameritech.net/users/knives/grits.htm
and
http://www.tedpella.com/material_html/charts.htm

I personally do the scary sharp thing but do use my waterstones on occasion for stuff that I find doesn't work well on my sandpaper. All this will change by the end of the week though when I have my clone of the LV Mark II finished. Should make flattening the backs of plane blades a bit faster.

Gotta get some of the LV 15,5 and .5 micron paper though.. looks pretty sweet.

For more on a good sharpening system and on plane blades and how they dull. See Brent Beach's site at:
http://www3.telus.net/BrentBeach/Sharpen/bevels.html

[Zahid Naqvi]

http://www3.telus.net/BrentBeach/Sharpen/bevels.html

Scott, this URL was great. I have read all the pages by Brent Beach, great ideas on the honing and sharpening jig. I will probably try to make one over this weekend.

Zahid

[Joel Moskowitz]

http://www.ameritech.net/users/knives/grits.htm
and
http://www.tedpella.com/material_html/charts.htm

These charts are one of the recent myths of woodworking.
You can produce equally sharp edges (on western steels certainly)
with oilstones, waterstones and sandpaper.
looking at that chart one would think that an arkansas stone at 1000 grit produces the same quality edge as a 1000 grit waterstone.

but it doesn't (the chrysal structures are different and they cut differently)

but you don't have to believe me or an ariticle in Pop Wood where the waterstone people compared results with the oilstone people and got the same quality edge.

If you could not get the sharpest edge needed for woodworking off of an oilstone all the fine woodworking from about 1850 when Arkansas stones first came on the market to about 1975 when waterstones first because popular couldn't have been built - but they were.

THere are tradeoffs of speed, maintenance, mess, inital and recurring costs between these technologies but the end result is the same. The important thing is learning the technique of sharpening and then you can sharpen on anything with anything.

[James Carmichael]

I use to use water stones but I got tired of always having to flatten them before the next sharpening cycle.

I've gone back to the "scary sharp" method and find that the 2000 grit wet/dry sandpaper equates to my old 8000 water stone.

At Red Hill Corporation I saw 2500 grit wet/dry paper but I didn't buy it. I felt 2000 was fine enough.

I'm just starting out and find Scary Sharp works quite well going up to 2000 grit. Rockler has 2500 grit self-adhesive in their fine sharpening kit.

I went to the same clinic (in Fort Worth) and was disappointed, about all they did was sharpen an iron on a Tormek. It was an eye opener, though, when I got to try an old Stanley #5 with a Hock iron, whew, that thing went like a knife through warm butter.

I figure if I go much further, one of the lower end low-speed sharpening systems like Delta or Baldor might be a good investment. So far, I've spent probably $40 on a jig, sandpaper and adhesive. With 5 sheets each of 800 - 2000 grit running about $14 at the local AutoZone, it won't take long to get up to the $100-$150 range that one of these would cost, and would also save time and mess. At $400, the Tormek is too much for a dedicated sharpener.

In the meantime, I plan to pick up a chunk of raw leather and give stropping a try.

[Scott Quesnelle]

James,
You might find a maple strop to work better than leather. Take a chunk of 3/4" ply and mount 1/4" thick slices of endgrain maple. plane it nice and flat and you have a strop that is nice and hard and should last you a life time. You might want to read Brent Beach's page on stropping though. Link is mentioned below.

Joel,

I agree that these charts don't give the whole picture. They do however show what the relative grit size is on each of the stones.

The cutting action of sandpaper, oilstones and waterstones are all different.

Waterstones are constantly showing new abrasives which will be the starting size of 14 microns, this means that the cuts in the steel will never be smaller than 14 microns. Waterstones (especially the newer man made ones) have a very consistent abrasive size.

The sandpaper isn't showing new abrasives like the waterstone, but the abrasives do dull and wear off of the sandpaper, this would slow the cutting action but also means that some of the abrasive particles could be smaller than 14 microns, but probably not, they just end up losing their 'sharpness' and not cutting anymore.

Oilstones are slow wearing, and as such the surface is being exposed slowly. Also, I believe the stone's abrasive particles break down into smaller and smaller pieces, so while the average size of the particles might be 14 microns. Being a natural material, there could exist a mixture of anything from 1 micron particles up to 20 micron particles. This would give you a better polishing action, since the smaller particles still cut.

As for the quality of 18th century work. I have seen craftsmen produce excellent work without a 'super' sharp edge. Also, what was used to produce the lovely work seen from the renaissance? What was used before arkansas stone was sold?

Overall, current woodworkers end up being far more anal about sharpening and trying to get a sharper edge, and with less work on the part of the woodworker.

Hey, I wil admit to falling into this trap. I am finishing off right now my clone of the Lee Valley mark II sharpening system. I want it to help me with some of the rough slog work when tuning up flea market blades.

Either way, sharpening is always a fun topic to talk about.

Scott